Made a stronger test for get_d_2exp.
Made a stronger test for get_d_2exp.

fredrik-johansson/flint2,jpflori/flint2,dsroche/flint2,wbhart/flint2,jpflori/flint2,dsroche/flint2,jpflori/flint2,wbhart/flint2,dsroche/flint2,dsroche/flint2,wbhart/flint2,fredrik-johansson/flint2,jpflori/flint2,fredrik-johansson/flint2